When you think of youtube, you may not think of wealthy celebrities cashing in on their fame. But you're about to meet some big-time stars with millions of fans and countless perks who made their names not in movies or TV shows but with internet videos and clicks. Here's ABC's David Wright. Edgy, sexy, glamorous, the bad girl look. Reporter: She is a human chameleon. Blend that color until you have a gradient finish. Reporter: With a worldwide audience. Her specialty -- makeup tutorials that demonstrate how to transform yourself into Barbie or lady gaga. I love this look. Have fun with it. Reporter: Or even the mother of dragons from "Game of thrones." Videos that have made Michelle Phan a huge star with a powerful brand. How many clicks? I think I'm at 800 million. I have to check again because it's always changing. Reporter: Many Phan is a prime example of a new breed of celebrities. Folks who are bypassing Hollywood, making millions on youtube. What makes youtube the perfect meed medium for me is I can have a two-way dialogue with my audience. Reporter: That Barbie video, 53 million views. That's a super bowl audience. An audience that's made her the ultimate cover girl with her own line of makeup. Hi, everyone. I'm Michelle Phan, and welcome to my youtube channel. Reporter: A new lifestyle network. And a growing list of endorsement deals. She and others helping to make youtube an entertainment powerhouse, a billion unique viewers a month. More than $5 billion in ad revenues. Figures that have every movie studio, TV network, and record label looking over their shoulders. We're not talking here about the one-hit wonders like -- or David after dentist. Is this real life? Yeah, this is real life. Reporter: The youtube a-listers are an eclectic bunch. There's fashionista Bethany motor. Choker necklaces are super cute. Reporter: There are any number of youtube chefs who could give Jamie oliver a run for his money. It smells so good. Smells like peanut butter heaven. Reporter: And it seems like this Swedish -- we're not quite sure what cutie pie is but it's big. All these incredible stars are emerging on this platform and in the digital space that have a hugely engaging and loyal audience, bigger than I'd say some of the networks and cable channels and shows and traditional stars. Reporter: Among them, epic rap battles of history, aka Erb. ? iPhone, iPad ? a channel that features high in the sky rap-offs. Albert Einstein rapping against Stephen hawking. Hitler against darth vader. ? Can't take anymore ? Miley Cyrus versus Joan of ark. ? Keep your party in the usa, viva la France ? Reporter: The guys behind Erb is peter shukovff and Lloyd alquist. Who used to be struggling comedians. You guys are youtube millionaires at this point, right? We're youtube million viewers. Is that not the same thing? No. A billion clicks overall? Yeah. But if those were burgers at McDonald's -- Yeah. Oh, yeah? Well, you're stupid. Reporter: Erb is so popular three of their raps are technically gold records. ? People that are in a garage band are still dreaming of playing the stadium. But I guess you guys are playing the stadium even though you're playing in your garage. Yeah. That's a pretty cool way to say it. We're playing the stadium from the garage. Reporter: They took us behind the scenes at maker studios, a youtube studio now owned by ABC's parent company, Disney. Not a single suit in sight. Are you making more or less money than you would make if you were doing this for, say, comedy zplernlt. We wouldn't be able to do this for comedy central. They never would have let some of the choices we made happen. Reporter: They won't say exactly how much they're making. Just that it's comfortable. If it's not too intrusive a question. No, please. How much is a click worth? A click is worth one smile. You're not going to give me an answer, are you? No, absolutely not. How many youtube millionaires are there? Oh, gosh. And who would they be? I would say 1%. Reporter: Michelle Phan is also purposely vague about how much money she's making. What is a click worth? Oh, it depends. It really fluctuates. It's like the stock market. Nobody will give me a straight answer. No. I'm being really honest. It really fluctuates. Reporter: She got her start right out of college when she was still figuring out what to do with her life. You posted your first video in 2007. You were how old? I was 21 years old. I thought probably like 50 people will watch this video. And then a week later I check in and I see 40,000. And I was thinking to myself, whoa, who are all these other people? Wholesale is watching this? Reporter: Now her videos are so popular she's able to build on that success. Youtube is a platform where you can share your gifts, your talents, your message. Then you can take it to the next level and build a real business. Reporter: She now has her own line of cosmetics called M through a partnership with L'Oreal. It's a gold mine. A way to get their products in front of a whole new generation of customers worldwide. With built-in advertising to boot. She's like a best friend, telling you how to apply makeup. So from L'Oreal's perspective she has a great quality of communicating. Do you feel like you're making what you should be making from these things? Absolutely. But you're not going to see me buying a ferrari or a mansion because that's not my lifestyle. Could you afford to if you wanted? I could actually. Reporter: Despite her mega stardom she is decidedly down to Earth. At one point during our interview helping me fix my makeup. She's that rarest of breeds, an a-lister who's still also an ingenue. I predict big things for you. I think you're going to go gangbusters. I just want to have fun. Reporter: The future belongs to her. Like I still have to pinch myself every once in a while. It really does feel like a dream come true. Awesome. It's a wrap. Reporter: I'm David Wright for "Nightline" in Los Angeles.

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